Exam 21: Public-Key Cryptography and Message Authentication

A hash function such as SHA-1 was not designed for use as a MACand cannot be used directly for that purpose because it does not rely on a secret key.

The DSS makes use of the _________ and presents a new digital signature technique, the Digital Signature Algorithm (DSA).

The __________ uses an algorithm that is designed to provide only the digital signature function and cannot be used for encryption or key exchange.

_________ are analogous to a burglar guessing a safe combination by observing how long it takes to turn the dial from number to number.

___________ was the first published public-key algorithm.

The one-way hash function is important not only in messageauthentication but also in digital signatures.

The Diffie-Hellman algorithm depends for its effectiveness on thedifficulty of computing discrete logarithms.

The National Institute of Standards and Technology has published Federal Information Processing Standard FIPS PUB 186, known as the __________.

A ________ attack involves trying all possible private keys.

Perhaps the most widely used public-key algorithms are _________ and Diffie-Hellman.

One of the first public-key schemes, _______, was developed in 1977 by Ron Rivest, Adi Shamir, and Len Adleman.

The _________ attack exploits the common use of a modular exponentiation algorithm in RSA encryption and decryption, but can be adapted to work with any implementation that does not run in fixed time.

SHA-1 is considered to be very secure.

If speed is a concern, it is fully acceptable to use _________ rather than SHA as the embedded hash function for HMAC.

The principal attraction of __________ compared to RSA is that it appears to offer equal security for a far smaller bit size, thereby reducing processing overhead.

Timing attacks are only applicable to RSA.

The purpose of the __________ algorithm is to enable two users to exchange a secret key securely that can then be used for subsequent encryption of messages.

NIST has published FIPS PUB 186, which is known as the ___________.

RSA is a block cipher in which the plaintext and ciphertext are integersbetween 0 and n - 1 for some n.

A __________ type of attack exploits properties of the RSA algorithm.